Improvement in paving-blocks



F. VDNVERSEN l. BICKEL.

Paving- Block.

Patented July 2 0-, 181.5.

ZZZ/61.72202! WM 8W UNITED STATES PATENT OFFICE FREDERICK VON VERSEN ANDJOHN BIOKEL, OF BALTIMORE, MARYLAND.

IMPROVEMENT IN PAVING-BLOCKS.

Specification forming part of Letters Patent No. 165,896, dated July 20,1875; application filed June 24, 1875.

To all whom it may concern:

Be it known that we, FREDERICK VON VERSEN and JOHN BIGKEL, of Baltimore,Maryland, have invented certain Improvements in Footwalks, of which thefollowing is a specification:

The object of our invention is to provide a footwalk which shall becheap, durable, pleasing in appearance, and impervious to. Water, andwhich shall also permit the water to flow from its surface withoutwetting the feet of pedestrians thereon.

The invention consists in the employment of blocks composed of protoXideof iron, ferruginous silica, and pulverized quartz or calcined clay,burned at a heat sutficient to vitrify the surface; in providing theblocks with longitudinal grooves in their edges to receive cement, forthe purposes of producing watertight joints and preventing displacementof the blocks; and in providing the upper face of the blocks withtransverse channels and beveled edges, in order to permit the water tofall below the surface and flow from the walk without wetting the feetof those walking thereon.

Figure 1 represents a perspective view of one of our blocks or tiles;Fig. 2, a vertical cross-section of a pavement composed of a series ofthe blocks.

in the manufacture of our blocks we prepare a compound consisting ofprotoxide of iron, ferruginous silica, and pulverized quartz or calcinedclay, in about the following proportions: Protoxide of iron, twenty-fiveparts; ferruginous silica, fifty parts; pulverized quartz, twentyfiveparts. The compound, properly tempered with water, is thoroughly mixeduntil a uniform mass is produced, and is then molded into blocks ofsuitable form, and baked or burned in a kiln or oven, the temperaturebeing finally raised until the surface of the blocks is vitrified, afterwhich they are permitted to cool gradually in order to avoid fracturingthe surface.

The blocks thus produced present a very hard and smooth surface, and arecompletely impervious to water, so that a pavement composed of them willnot absorb or retain moisture, and consequently will neither remainmaterial.

damp and cold nor be subject to breakage in frosty weather, as is thecase with those composed of brick and similar porous absorbent Theblocks may be molded of any size and form desired, and, when required,coloring material of any suitable character may be introduced into thecompound before it is molded.

In order to render pavements composed of our blocks perfectlywater-proof, we provide the edges of the blocks with longitudinalgrooves, 0b, to receive hydraulic or other cement, which is introducedbetween the blocks at the time of laying them in place. The cement, inaddition to preventing the passage of moisture between the blocks,serves also to hold the edges of the blocks in position, and prevent thesurface of the pavement from becoming uneven.

In order to facilitate the flow of water from the pavement, and toprevent the same from flowing across the surface and dampening the feetof pedestrians, we provide the blocks with transverse channels I) intheir upper faces, and also bevel their upper edges, so as to producechannels between the adjacent blocks, as shown in the drawing. Thewater, flowing down into thechannels, readily escapes from the pavementwithout passing over and wetting its surface.

While it is obvious that the grooved sides, the channels, and thebeveled edges are advantageous features, they may either or all of thembe dispensed with. While it is obvious that any suitable clay may beemployed after adding thereto the lacking ingredients of the compound,it is, of course, desirabie to employ a clay having in a natural statethe nearest resemblance to the required compound.

What we claim as our invention is-- A paving block or tile composed ofthe ingredients hereinbefore stated, and burned until a vitreous surfaceis produced, with or without the grooves a and channels b, or either ofthem.

FREDERICK VON VEBSEN. JOHN BIGKEL. Witnesses:

P. T. DODGE, W. O. DODGE.

